The present invention relates to a metal-encapsulated gas-insulated high-voltage installation with an overvoltage arrester which is likewise accommodated in a separate gas-filled encapsulation which is connected to the encapsulation of the high-voltage system by means of a gas-tight feedthrough and comprises means which, after having responded, blow the arc from its housing into the encapsulation.
Such a metal-encapsulated gas-insulated high-voltage installation which may be a high-voltage switch gear or a high-voltage line, is known from DE-AS No. 22 47 996 corresponding to U.S. Pat. No. 3,875,466. In the known high-voltage installation, the separate encapsulation is filled either with air or a gas advantageous for the operation of the overvoltage arrester; however, it can also be filled with the same gas which is provided for the insulation of the entire system, particularly SF.sub.6. The overvoltage arrester is of conventional design and consists of spark gaps and voltage-dependent resistors or metal oxide resistors without spark gaps. It is furthermore provided with means which, if it is overloaded, allow the arc to leave its housing so that the arc then burns in the encapsulation between the overvoltage arrester and the wall of the encapsulation. Normally, the current load is relatively small if the overvoltage arrester responds upon being triggered by overvoltages. If however, a defect arc is brought about by an overload of the overvoltage arrester, very large currents can flow which stress the branch with the overvoltage arrester by large dynamic forces and can result in damage or destruction of the overvoltage arrester and possibly of the feedthrough.